JV153 wrote: However, there have been some serious declines in US conventional gas production and I doubt US nat gas prod will ever much surpass it's current levels.
And the same was said after the US natural gas peak in the early 1970's as well. Oops. And then there was the natural gas cliff in America in 2005. Oops. So now someone wants to claim the same thing which hasn't worked out so well for the past half century? Okey Dokey.
The fundamental belief of scarcity running out arguments is that today is always as good as it can get. Until it isn't. And then claim the same thing at the next high point. Continue until substitution clobbers the old idea, and then begin proclaiming the same thing about whatever clobbered it. Rinse and repeat.
Forget not the lessons of the great gasoline scare of 1916, lest your great great grand children say the same thing about this generations portents of Doom!